Method of and turf product for erosion control

ABSTRACT

A turf product for use in erosion control is provided as a turf product matting of a fibrous material in combination with a reinforcing mesh for giving directional stability thereto. Turf is located above the matting and the reinforcing mesh with its root system passing thereinto. The turf is initially grown above the matting and the reinforcing mesh with its root mass passing therethrough onto an impervious surface. The impervious surface acts as a barrier to root transmission, so that the roots tend to mat above the impervious surface, and when the turf product is moved to its required location for use, the roots are then permitted to pass into an underlying surface.

BACKGROUND OF THE INVENTION

1. Technical Field of the Invention

This invention relates to a method of erosion control and a turf productwhich is specifically adapted for use in the erosion control area.

2. Description of the Prior Art

It is often desirable to retain soil in areas where erosion is likely,say, in banks or cuttings or the like around roadwork so that the areacan be stabilised and growth can be encouraged and subsequently act tobind the soil of the area against later damage.

Various approaches have been taken to do this. For example, the locationof a netting fabric over the surface, placing other material, such as,say, wood chips over the surface and possibly retaining these with anetting or the like and direct planting of shrubs or the like onto thesurface.

If it has been required to grass the surface, this has been done byplacing turf thereover but, in general terms, this has not necessarilybeen completely successful.

SUMMARY OF THE INVENTION

The principal object is to provide a turf product which can be used invarious applications but which is particularly useful in the erosioncontrol area and also to provide a method of erosion control whichbasically uses this turf product.

In its broadest sense, the invention includes a turf product comprisingmatting of a fibrous material in association with a reinforcing mesh togive directional stability thereto, and turf located above the mattingand mesh with its root system passing thereinto and adapted to passtherethrough and into an underlying surface.

This combination provides a product which has good stability and canreadily be handled but which, once located, is readily retained in itslocated position.

The invention also includes a method of manufacturing a turf productwhich includes the provision of an impervious layer, locating a rootmatting on the layer in association with a reinforcing mesh or the like,and locating thereover turf, the roots of which can pass through themesh and matting combination and can provide a stable and strongproduct.

It is preferred that the turf is located on the mesh and mattingcombination in the form of a washed turf having a strongly formed rootsystem but it would be possible to grow turf thereon either from seed orstolons if this is required.

The invention also includes a method of erosion control comprisingpreparing the surface to be protected and laying on this surface a turfproduct as hereinbefore described, the arrangement being such that theproduct will tend to remain on the surface without moving, although itcan be pegged or otherwise connected thereto or could be top dressedwith sand or soil to ensure that there was no movement, the arrangementbeing such that the root system of the turf passes through the mattinginto the ground's surface to thereby consolidate the surface.

In order that the invention may be more readily understood, we shalldescribe the formation of the product, the product itself, and its use.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

Particular embodiments of the turf product will be described in terms ofthe accompanying drawings:

FIG. 1 is a schematic representation of a jute matting incorporating areinforcing mesh.

FIG. 2 is a schematic representation of an embodiment of the turfproduct with turf growing through a reinforcing mesh and an underlyingmatting.

DETAILED DESCRIPTION OF THE DRAWING AND PREFERRED EMBODIMENTS

In a preferred form of the turf 60 product turf, preferably in the formof washed turf, is lain (FIG. 1) over jute matting 10 which incorporatesas an integral part thereof a plastic reinforcing mesh 20 which iseffectively sandwiched between the upper 11 and lower 12 sides of thejute matting.

Although in this preferred embodiment jute matting is used it may be ofsisal or could even be of plastic or any other appropriate fibres. Theform and thickness of the mat can also vary depending upon the requiredstrength of the completed product as can the reinforcing mesh.

Thus the precise material of the matting is not germane to thisinvention except that it is preferred that it be of some fibrousmaterial, through which roots can readily pass, and which will of coursemat appropriately. In addition the exact material of the reinforcingmesh can be varied as can the particular design of such a mesh althoughin this preferred embodiment of the invention the mesh has rectangularplastic elements.

In another embodiment of the invention (FIG. 2) a reinforcing mesh 30,which includes an underlying mesh layer 32 affixed to an overlyingconvoluted mesh layer 31, is positioned on a fibrous layer 40. The turf60, preferably washed turf, is then positioned over the top of thereinforcing mesh layer such that its roots 41 subsequently grow throughboth the reinforcing mesh layer 30 and the fibrous layer 40 and are thenable to penetrate into the ground 50 and bind the turf product to theground.

Again the types of mesh and fibre used can be of any appropriate kindhowever a plastic reinforcing mesh of any chosen shape and a jutematting are preferred.

It is also preferred that the product be initially grown on animpervious surface 70 (FIG. 1) and a plastic sheeting surface or thelike can be provided which acts to control water flow but which, at thesame time, acts as a barrier against root transmission. In each of theembodiments described above the turf product can be grown above such animpervious layer.

If required, we could put top dressing such as sand on the turf, but inmost applications this would not be necessary. The turf is thenpermitted to grow, under controlled or more or less controlledconditions to facilitate growth as much as possible. That is, a specificwatering regime may be used and, if required, fertiliser can be appliedto the surface, normally with the water.

We find that the root system of the turf rapidly passes through the meshand mat combination and contacts the plastic or other impermeablesurface, and tends to mat by moving along the area between the fibrousmat and the plastics material.

At this stage, there is provided a product which is inherently strong,the reinforcing mesh giving it directional stability and the combinationof the roots and the mat providing an overall structural rigidity.

At that time, the product can be rolled and prepared for transport.Depending on the distance for transport and other parameters, theproduct may well be treated with chilled water before rolling, to bringthe overall temperature down, and, after rolling, particularly ifambient temperatures are high or the distance to be travelled is great,could be placed in a refrigerated container or the like.

In use, it is only necessary to prepare the surface over which theproduct is to be laid, locate it, and unroll the product. Where thereare a number of rolls being used, to make contact between the adjacentends and sides of the rolls.

Depending on the surface on which the product is being located, it canbe held relative to the surface by pins or pegs which pass through theproduct into the surface.

Because of the overall formation of the product and, specifically thereinforcing mesh, any tendency to move will be resisted, and because ofthe general weight of the product, this may be all that is required.

Alternatively, or as well, the product may be top dressed with sand orsoil to provide additional weight and to act to further preventmovement.

As the root system enters the ground's surface then the product itselfwill resist any form of movement and, ultimately, there will be a highdegree of binding between the surface and the product will then becomeintegrally fixed to the surface.

If the product is being used on a relatively flat area, then, of course,it may well be unnecessary to take any steps whatsoever to hold theproduct.

It will be seen that the product of the invention is basically simple inconcept but enables a ready method of consolidating surfaces vulnerableto erosion and particularly surfaces which would be difficult to grass,either by growing grass from seed or planting stolons, in both of whichcases, should there be any rain, the seed in particular, can be washedoff the surface and there can be erosion before there is sufficientcoverage. With normal harvested turf, which does not have the structuralrigidity of the turf product of the invention, there would be a tendencyfor movement under these circumstances.

What is claimed is:
 1. A turf product matting comprising a fibrousmaterial in combination with a reinforcing mesh for giving directionalstability thereto, and turf located above the fibrous material and thereinforcing mesh with its root system passing thereinto, the turf beingpre-grown turf having is roots washed free of soil, initially beinglocated on the surface of the fibrous material, the root mass beingpermitted to grow and pass through the fibrous material and thereinforcing mesh onto an impervious surface which acts as a barrier toroot transmission, so that the roots tend to mat above said impervioussurface for providing, in combination with the fibrous material and thereinforcing mesh, structural rigidity for enabling the turf product tobe readily moved to its required location, at which the root mass passesinto an underlying surface.
 2. A turf product as claimed in claim 1 inwhich the reinforcing mesh is incorporated within, and is integral to,the fibrous material.
 3. A turf product as claimed in claim 1 in whichthe turf is located above the reinforcing mesh which is positioned onthe fibrous matting with the root mass of the turf passing through boththe mesh and the matting.
 4. A turf product as claimed in claim 1 inwhich the fibrous matting is of jute.
 5. A turf product as claimed inclaim 1 in which the turf is a turf layer.
 6. A turf product as claimedin claim 1 in which the turf is washed turf.
 7. A turf product asclaimed in claim 6 in which the turf is grown from seeds or stolons. 8.A turf product as claimed in claim 1 wherein when the turf is grown, theturf product is able to be rolled and packaged for transport to a remotesite for use.
 9. A turf product as claimed in claim 1 wherein when theturf product is moved to its required position, the turf product is thenaffixed to the underlying surface.